Gelating pad for duplicators



April 2, 1935. AR EV 7 1,996,582

GELATIN PAD FOR DUPLICATORS Filed March 16, 1932 2 Sheets-Sheet 1Inciflibr Qffed Marcfwu,

April 935. A. MARCHEV v l,?96,582-

GELA'IIN PAD FOR DUPLICATORS Filed March 16, 1932 2 Sheets-Sheet 2Patented Apr. 2, 1935 GELATIN PAD FOR nortioa'rons Alfred Marchev, LaGrange, 11]., assignor to Ditto, Incorporated, Chicago, 111., acorporation of West Virginia Application March 16, 1932, Serial No.599,214 g Claims.

: The invention relates generally to improvements in gelatin'pads andthe like and more particularly is concerned with the provision of ametal strip having novel means whereby the 5 same may be readily andsecurely attached to an edge of a pad or band such as are used inhectograph machines.

An object of the invention is to provide a metal strip having a novelconstruction rendering the same readily attachable to a pad or othersimilar article as may be desired without the use of special tools andwherein the union effected by reason of the special construction will(be particularly secure and able to withstand'considerable tension.

A further object is to provide a metal-reinforcing strip from a singleblank having fastening lugs integral therewith and a formed portion,which latter will co-operate with thearticle to which the strip isattached in a mannerto con siderably increase the efiiciency of theunion.

The gelatin pads and bands with which the present invention isparticularly concerned are used on duplicators to provide theduplicating surface and it is required that the bands be readilyattachable to securing means provided for'the purpose. Openings are alsoformed in the material of the pads adjacent the end strips for thepurpose of increasing their utility by rendering them adaptable tomachines of various makes.

It is therefore another object of the invention to provide an improvedconstruction of gelatin pad particularly designed for rotaryduplicatorshaving a novel attaching strip for detach-.- ably securing the ends ofthe pad to supports and openings therein positioned and arranged topermit means to extend through the pad for facilitating the stripping ofthe duplicated sheet therefrom.

With these and various other objects in view the invention may consistof certain novel feetures of construction and operation as be more fullydescribed and particularly pointed out in the specification, drawingsand claims appended hereto.

In the drawings which illustrate an embodiment of the device and,wherein like reference characters are used to designate like parts-Figure 1 is a perspective view showing a gelatin pad equipped with endstrips constructed in accordance with the present invention;

Figure 2 is a perspective view of the metal strip of the inventionshowing the fastening lugs formed integral therewith;

Figure 3 is an enlarged cross sectional view taken transversely of thestrip between the lugs; Figure 4 is an enlarged cross sectional viewshowing the strip in attached relation with an end of a gelatin pad.

Figure -5 is an elevational view of a drum such -5 as employed in rotaryduplicators, the same being shown equipped with securing means forgelatin pads as described; and

Figure 6 is an end view ofthe drum looking toward the right in Figure 5.10

The present invention is shown as applied to a gelatin pad Ill such asare used in hectograph machines for providing the duplicating surface,the pad being constructed of a fabric backing I2 having one surfacecovered with a. layer of 15 gelatin It. Although the advantages derivedfrom the improved construction of metal strip are particularlyapplicable to gelatin pads such as disclosed the invention is in nomanner limited thereto but has a considerably wider range since 2 thesame may be employed with equal efficiency 1 as end reinforcements forbands and generally any length of fabric or similar material wherein itis desirable thatstrips of the kind disclosed be secured to its edges.25

The metal strip is formed from a single blank of metal which is bentalong an edge It lon itudinally of the strip forming a portion l8 and aportion 2 of substantially equal width. The portion l8 has a pluralityof lugs 22 formed integral 30 therewith, being struck from the metal ofthe blank, resulting in providing a plurality of apertures 26 in portionI8. In order to materially strengthen this portion and to add to therigidity of the metal strip as a whole the apertures 24 are 5 sopositioned with respect to edge 26 of portion l8 as to leave a strip ofmetal 28 connecting sections 30 located on the respective sides of theaperture. Connecting the sections 30 in this manner materially increasesthe holding power of 40 the strip when the same is attached to a gelatinpad since the portion I8 is substantially one piece, whereas, in theevent the connecting strips 28 were omitted, it will be appreciated thatthe portion l8 would comprise a plurality of independent 45 sections 30.v I

.A feature of the present invention, among others, is the specialformation given to the portion .20 which is ribbed as at 32longitudinally of the portion, displacing sections of the portion 50 sothat the same lie in different planes forming an angle with each other,the apex of the angle at the rib 32. It will be seen from Figure 3 thatby reason of this special formation of portion Zd'the inner surface ofthe same is 5 provided with a bead 34. For attaching the metal strip asdescribed to an end of the gelatin pad In the same is located betweenthe portions l8 and 20 of the strip and after aligning the same withrespect to the band the portions are forced together, functioning asjaws and gripping the material of the pad between them. Preferablyportion I8 is forced in a direction toward the portion 20 since thisautomatically serves to increase the spacing between the lugs 22 and theportion as clearly shown in Figure 4. By the formation of thelongitudinal ridge in portion 20 of the strip the longitudinal bead 34is provided, the same projecting from the surface of the por- .tion andby crimping the strip upon an edge of the pad the inner surfaces of theportions are forced into contact with the surface of the pad with thebead being forced into the material to an extent such that the materialis securely united thereby to the strip.

The bead in effect forms a restricted passage serving to concentratepressure at that point whereby the material engaged is securely held andseparation of the parts by the material pulling out from the stripthrough tension is" prevented since in addition to the holding caused bythe material in contact with the bead it is correspondingly difiicultfor the material not so engaged to be drawn through therestrictedpassage. Thusthe union eflected between. the strip andmaterial has increased efficiency in respect to the ability of the partsto withstand tension by reason of the special formation given theportion.

Also the metal strip as constructed has utility as a reinforcing endmember for pads, bands or other analogous articles and also in providinglugs which may be employed as hooks should it be desired to attach thearticle to a support. The lugs being struck from the metal of the stripare integral therewith and are well able to withstand the tension placedon them in the stretching generally given the pads in order that theywill lie fiat and present a smooth surface. Also the retaining of asection of metal as a connection between sections alternating with theapertures results in materially adding to the strength of the union whenthe strip is attached to the pad and to the rigidity of the structure asa whole.

Figures 5 and 6 show a drum of a rotary duplicator with a gelatin pad ofthe construction described above detachably secured thereto. The drum isformed of spaced end members 35 and 37 having an inwardly directedperipheral flange 38 to which is secured the arcuate plate 40 extendingfrom points substantially diametrically opposite each other andproviding the support for the gelatin pad. The ends of the plate 40 arebent inwardly as at 4| and 42, respectively, the latter providing anedge over which is located the lugs 22 of the metal strip forming thatend of the pad, the body of the same being supported upon the arcuateplate 40 so that the gelatin covering l4 provides the duplicatingsurface of the drum. The other end of the band lies over the end 4| andis secured to shaft 43 by interlocking the lugs of the end strip withthe edge 44 formed integral with and extending the length of the shaft'43. In order that the pad may be held on the plate 40 in stretchedcondition shaft 43 is rotatable in the end members of the drum and maybe rotated by the operator by actuation of the finger piece 45 suitablys ecured to the shaft. The pawl 46 pivoted to end member 36 by stud 41has engagement with the ratchet 48 mounted on shaft 43 and in connectionwith the tension spring 50 serves to hold the shaft in rotated position.The operator may readily release the pawl 46 when it is desired torotate the shaft for the purpose of removing the gelatin pad by graspingthe finger piece 5| integral with the pawl.

The gelatin pad shown in Figure 1 in addition to having its endsreinforced by securely attaching thereto the metal strips described isprovided with openings 52 arranged in spaced relation at both ends ofthe pad adjacent to the strips. The openings are necessary in order topermit the deflecting fingers 53 to extend through the material of thepad, it being of course understood that similar openings are provided inthe depending end 42 for the same purpose. The shaft 54 journalled inthe end members of the drum is resiliently urged by the coil spring 55in a direction to maintain the fingers secured to the shaft by screws 56in a retracted position where they lie below the periphery of the drum.During rotation of the drum to perform a duplicating operation the shaft54 isrocked through lever 51 in a direction to project the fingers 53above the duplicating surface and since the duplicated sheet has itsleading marginal edge located over the fingers the edge is thereforelocated between the stripping rollers, which function to complete thestripping of the sheet. It will be clear from the foregoing that inorder to accommodate the deflecting fingers it is required that the bandhe provided with openings and with the present construction of pad thesame are arranged with respect to the end attaching strips to render thepad reversible and to also permit use of the pads in rotary duplicatorsof other types.

It is to be understood that I do not wish to be limited by the exactembodiment of the device shown, which is merely by way of illustrationand not limitation, as various and other forms of the device will beapparent to those skilled in the art without departing from the spiritof the invention or the scope of the claims.

I claim:

1. A gelatin pad for rotary duplicators having a rotating drum, said padbeing applied to the drum for providing the duplicating surface thereof,end members secured to the pad, lugs on the members for effectingsecurement of the pad to the drum, the pad having openings positionedadjacent the end members for permitting means carried by the drum toproject therethrough.

2. A duplicating pad comprising, in combine.- tion: a band of fibrousmaterial; a. gelatinized surface carried by said band; a metallic clipapplied to each end of said band; each clip compris-- portion of theclip, impressed into the material.

of the band; hook members struck out from the material of one of thefolded portions of the clip for attachment of the pad assembly to aduplicator drum; said pad assembly formed with openings adjacent eachclip bearing end for passage therethrough of paper deflecting fingers ofa duplicator drum. v

3. A duplicating pad comprising, in combination: a band of fibrousmaterial; a gelatinized surface carried by said band; a metallic clipapplied to each end of said band; each clip comprising an integral stripof metal folded upon itself and holding an end of said band clampedbetween the portions of the fold; a bead formed in one portion of theclip, impressed into the matethrough of paper deflecting fingers of aduplicator drum 4. A duplicating pad comprising, in combination: a. bandof fibrous material; a gelatinized surface carried by said band; ametallic clip applied to each end of said ban; each clip comprising anintegral strip of metal folded upon itself and holding an end of saidband clamped between the portions of the fold; and hook membersprojecting from one of the folded portions of the clip for attachment ofthe pad assembly to the duplicator drum; said pad assembly formed withopenings adjacent each clip bearing end for passage therethrough ofpaper deflecting fingers of.

a duplicator drum.

5. A duplicating pad comprising, in combination: a band of fibrousmaterial; a gelatinized surface carried by said band; a metallicreenforcing member applied to each end of said band; each reenforcingmember comprising opposed layers of metal clamping the fibrous materialbetween them; and hook members projecting from one of said layers of thereenforcing member for attachment of the pad assembly to a duplicatordrum; said pad assembly formed with openings in each reenforcing memberfor passage therethrough of paper deflecting fingers of a duplicatordrum.

ALFRED MARCHEV.

